EP 0 363 832 discloses an UV high-power radiator having elongated electrodes connected in pairs to the two terminals of a high-voltage source. In this case, the electrodes are separated from one another and from the discharge chamber of the radiator by dielectric material. Furthermore, the elongated electrodes are arranged alternately next to one another with different polarity (anodes and cathodes), it being possible in this way to realize planar-like discharge configurations with relatively flat discharge vessels.
WO 94/23442 discloses a method for operating an incoherently emitting radiation source, in particular a discharge lamp, by means of dielectrically impeded discharge. The operating method provides for a sequence of active power pulses, the individual active power pulses being separated from one another by dead times. Here, in the case of unipolar pulses a multiplicity of individual delta-shaped discharges lined up along the elongated electrodes are formed. The advantage of this pulsed mode of operation is a high efficiency in the generation of radiation.
If, now, the method of WO 94/23442, for example, is applied to the flat radiator of EP 0 363 832--as already described in DE-A 195 26 211--, it is found that the individual discharges are formed only between the anodes and one of the two respectively directly neighbouring cathodes. It cannot be predicted by which of the two neighbouring cathodes the discharges will be formed in each case. Discharges which burn from neighbouring cathode strips onto one and the same anode are not observed. Referring to the flat radiator as a whole this results in a non-uniform discharge structure. A further disadvantage is the fact that the power density is limited by the phenomenon outlined.